Lowercasing table and column names   

--This generates SQL you can then run - lower case column names - this puts the sql in a single record 
-- suitable for running in a single EXECUTE statement or cut and paste from PgAdmin query window
SELECT array_to_string(ARRAY(SELECT 'ALTER TABLE ' || quote_ident(c.table_schema) || '.'
  || quote_ident(c.table_name) || ' RENAME "' || c.column_name || '" TO ' || quote_ident(lower(c.column_name)) || ';'
  FROM information_schema.columns As c
  WHERE c.table_schema NOT IN('information_schema', 'pg_catalog') 
      AND c.column_name <> lower(c.column_name) 
  ORDER BY c.table_schema, c.table_name, c.column_name
  ) , 
   E'\r') As ddlsql;
   
-- As David Fetter kindly pointed out, this looks cleaner, returns one record per ddl and is more psql friendly
SELECT  'ALTER TABLE ' || quote_ident(c.table_schema) || '.'
  || quote_ident(c.table_name) || ' RENAME "' || c.column_name || '" TO ' || quote_ident(lower(c.column_name)) || ';' As ddlsql
  FROM information_schema.columns As c
  WHERE c.table_schema NOT IN('information_schema', 'pg_catalog') 
      AND c.column_name <> lower(c.column_name) 
  ORDER BY c.table_schema, c.table_name, c.column_name;

--lower case table names - the PgAdmin centric way, single EXECUTE way
SELECT array_to_string(ARRAY(SELECT 'ALTER TABLE ' || quote_ident(t.table_schema) || '.'
  || quote_ident(t.table_name) || ' RENAME TO ' || quote_ident(lower(t.table_name)) || ';'
  FROM information_schema.tables As t
  WHERE t.table_schema NOT IN('information_schema', 'pg_catalog') 
      AND t.table_name <> lower(t.table_name) 
  ORDER BY t.table_schema, t.table_name
  ) , 
    E'\r') As ddlsql;
  
-- lower case table names -- the psql friendly and more reader-friendly way
SELECT 'ALTER TABLE ' || quote_ident(t.table_schema) || '.'
  || quote_ident(t.table_name) || ' RENAME TO ' || quote_ident(lower(t.table_name)) || ';' As ddlsql
  FROM information_schema.tables As t
  WHERE t.table_schema NOT IN('information_schema', 'pg_catalog') 
      AND t.table_name <> lower(t.table_name) 
  ORDER BY t.table_schema, t.table_name;

--generates something like this
ALTER TABLE public."SPRINT" RENAME TO sprint;